What is stereo?




There are now two system of high fidelity, monophonic (monaural) and stereophonic. Monophonic is a system that starts from one microphone and is fed through a single high fidelity set. Stereophonic is a double system. Two separate microphones are placed at different sides of the orchestra and two different systems are used to keep the two signals or channels separated. Two separate speakers are used, placed on different sides of you room. Stereo is much like 3-D photography, two slightly different sound reach your ears giving you a new dimension in sound.




H.H. Scott '59





JVC FX-1010TN


Computer-Controlled Digital Synthesizer Tuner
The primary function of a tuner is bring in the station you want precisely and accurately, whether it's near or far. Using the latest circuit designs and device, we've made our tuner from the Super Digifine series, the FX-1010TN, more sensitive, selective and interference resistant than ever - the reason the tuner is able to provide wide dynamic range, low noise and low distortion, and wide frequency response. It's also extremely easy to use, thanks to the amazing power of an advanced microprocessor.

Reception servo for optimum reception from any station, almost anywhere. A built-in microprocessor detects the strength of a tuned station and compares it against the degree of interference from adjacent stations. Then, depending on the degree of interference, the microprocessor selects the optimum operation mode for front-end. IF and multiplex decoder stages (adjusting such parametersas RF gain, IF bandwidth, Quieting Slope Control and mono/stereo). Therefore when interference is excessive, a narrow IF bandwidth is automatically chosen to prevent noise. And if there's no interference, then a wide IF bandwidth is automatically selected to give you remarkably clear sound. When a signal level is overly strong, the RF gain is reduced to avoid saturation distortion; when it's weak, sensitivity is increased. Moreover, the tuner is equipped with inpuls to connect two antennas; each may be oriented for the best reception of stations in diametrical opposition to the other .
Conveninlly, the position of antennas, A or B, may be stored in memory station by station, which allows most precise reception from any station, without multipath distortion.
To add to convenience, the selected parameters are clearly indicated on a large fluorescent display, letting you quickly confirm tuning status.

Features for low noise and low distortion
JVC uses components and devices to ensure lowest possible noise and distortion and widest dynamic range from your favorite stations.
"Opticalink" System
This system is one developed by JVC to ensure highest purity from your favorite station. It uses eleven photocouplers (each consisting of a photoemitter and photosensor) to electrically decouple the analog from the digital section. As a result, interference between the two due to electric coupling is completely eliminated. This puts an end to digital noise and removes any trace of muddiness from the sound you hear.
In the FX-1010TN, each of the analog/tuner, digital control and "Opticalink" sections is mounted on its own PC board to shut outmutual interference and noise. And the digital control section, which can be a source of noise generation, is fully shielded to contain noise.

MOS FET front-end
The front end employs a dual-gate MOS FET which, along with high-Q varicaps, makes it as sensitive, selective and resistand to interference as a front end using an elaborate 5-ganged tuning capacitor. Therefore, the Signal-to-Noise ratio and interference rejection capability are outstanding.
Low-distortion IF section
The IF section of the FX-1010TN features ceramic filters coupled with a distortion reduction circuit for better phase response and low distortion
PLL detector and Beatless PLL multiplex circuit.
A PLL detector combines low distortion and high Signal-to-Noise ratio for dynamic and wide-range sound. Also the FX-1010TN uses a new PLL multiplex circuit that electrically filteres out beat noise-noise resulting from two or more frequencies interfering with one another. In a conventional CR-type MPX circuit using a VCO (Voltage Controlled Oscillator), however, a device called an "anti-birdie filter" is used to remove beat noise, but the coils in the circuit tend to degrade signal qulaity. In our beatless multiplex circuit, moreover, a pilot canceller is featured to suppress the leakage of the pilot signal, thus obviating the need for a 19 kHz filter, another component that would harm sound quality.
Active Filter
To prevent leakage of the 38 kHz subcarrier contained in a stereo broadcast, an LC filter built from coils and capacitors is commonly used, but, due to the magnetic distortion the core of the coil causes, this system tends to degrade sound quality in the FX-1010TN, however, an active filter; with coil eliminated, it provides better high-frequency response, wider separation and higher Signal-to-Noise ratio.

Computer-controlled operating ease.
With the help of powerful microcomputers, we've also improved tuning ease of the FX-1010TN tremendously.
Station name display
You can assign up to six alphanumeric characters to each preset station in the memory - "JAZZ-B", for instance.
Auto memory
All 40 FM/AM stations can be automatically tuned in sequence and committed to memory as presets.
Random preset memory
You can preset as many as 40 FM/AM stations in random oredr. There's numeric keypad that allows direct access to any of 40 stations.
Preset scan
All preset FM/AM stations can be automatically sampled one by one for approximately 5 seconds each
Preset cancel
Use this feature to skip undesired preset stations during preset scan
Program memory
Up to eight "events" (broadcasts) can be programmed for sequential recall under the control of an optional timer.
Auto QSC
The Auto Quieting Slope Control circuit automatically goes into action to reduce noise when a station signal is weak.
dB-referenced signal strength indicator
Read off the signal strength of a tuned station accurately down to 1 dB - a convenience when orienting antennas.
Variable stop level
Adjust FM/AM muting threshold in 5 dB steps over a range during auto tuning. The variable stop level feature lets you adjust the threshold from 20 dB to 60 dB for FM, and from 60 dB to 90 dB for AM. When you use a higher level, you'll receive only powerful, clear-sounding stations, with weak stations muted out. Or, when you choose a low level, all receivable stations are tuned in.
Record calibration signal generator
Record calibration signal generator outputs a standard 400 Hz signal for recording level adjustment.so, you can easily set the recording level for different broadcasts or types of tape.

Specifications:
FM Tuner Section (IHF)
Usable Sensitivity:  10,3 dBf (0,9 µV/75 Ω)
50 dB Quieting Sensitivity:
Mono :  14,8 dBf (15 µV/75 Ω)
Stereo :  38,1 dBf (22 µV/75 Ω)
Signal-to-Noise Ratio (IHF-A Weighted)
Mono / Stereo (aat 85 dBf) :  94 dB / 88 dB
Total Harmonic Distortion (1 kHz): 
Mono / Stereo :  0,009% / 0,02% (WIDE)
Capture Ratio:  1,2 dB
Selectivity (400 kHz):  25 dB (Wide); 75 (Narrow)
IF Response Ratio:  110 dB
AM Suppression Ratio:  65 dB
Stereo Separation (1 kHz):  60 dB (Wide)
Frequency Response:  20 Hz - 15 kHz (+0,3  -0,5 dB)
Antenna Input Impedance:  75 Ω unbalanced x 2
Output Signal Level:  600 mV (2,2 k ohms)
Rec Cal Output Level:  equivalent to 50 % FM modulation
AM Tuner Section
Usable Sensitivity :  250 µV /m (loop antenna)
Total Harmonic Distortion:  0,3%
Signal-to-Noise Ratio:  50 dB
Selectivity (±10 kHz):  35 dB
Image Response ratio:  40 dB
IF Response Ratio:  60 dB
Dimensions (W xH x D):  435 x 100 x 298 mm (17-3/16" x 3-15/16" x 11-3/4")
Weight:  3,7 kg (8,2 lbs)

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